Shot blasting nozzle



April 6, 1948. J. o. ALMEN SHOT BLAST-ING NOZZLE Filed Nav. 1, 1945 Zinnentor in (Q @L5/26W Gttomeg Patented Apr. 6, 1948 suor LAs'rlNe NozzLE John 0. Almen, Royal Oak, Mich., assigner to General Motors Corporation, Detroit, Mich., a

corporation of Delaware Application November 1, 1945, Serial No. 626,065

Claims.

This invention relates to the art of shot peening. Cold working of lmetal articles to compact the surface layer by shot peening is easily accomplished if the surface can be exposed to the shot blast. Existing equipment is unsuited to the peening of interior surfaces `of openings and cylinders and other out of the way places.

An object of the present invention is to provide lan improved tool for shot blasting interior surfaces including those of narrow deep holes into which the tool can be inserted axially and which tool includes as an important feature a rotatable deiector adjacent the nozzle to direct the blast substantially normal to the surf-ace and by continuous ,deector rotation relative to the nozzle will sweep the entire circumference once or repeatedly as may be desired. Continuous rotation of the deflection in the same direction may be done concurrently with axial travel of the tool within the opening to perform a peening operation over the entire interior surface in one stroke. A deector plate `and detachable mounting has been designed for easy and quick replacement, at low cost since the deector surface is rapidly Worn by the blasting material and must be frequently replaced.

A preferred embodiment of the invention is shown in the accompanying drawing illustrating .in Figure 1 a nozzle partly in section, for attachment to the ordinary air type shot or sand blasting machine and in Figure 2 a detail elevation of the defiector and associated parts.

In the drawing the inner tube l is connected, as by means of |a pipe or a flexible hose, to a source of high pressure iiuid, such as air or a liquid solution and the uid flows into a Venturi shaped nozzle tip 2. The tip 2 is secured in the end of a hollow body 3 having at its rear end a duct ll joined by a suitable pipe or flexible hose to a receptacle containing shot, sand or other solid particles of appropriate material and size for the particular operation to be performed. Fluid flowing into the Venturi shaped nozzle 2 creates a partial vacuum within the chambered body 3 and draws the shot through the duct 4 for entrainment in the high pressure fluid stream discharged from the nozzle tip 2. A set screw 5 retains the pressure delivery tube l in selected settings with respect to the Venturi shaped nozzle 2 and enables varying degrees of vacuum to be produced as required.

Directly in the path of discharge from the nozzle 2 is a deilector, preferably in the nature of a hardened steel plate E, supported by an adjustably mounted sleeve 1 rotatably and slidably telescoping the body 3. Such mounting enables the deilector to be shifted both axially and rotatably in relation tol the main body 3 and to be turned continuously or to any desired angle about the axis of the tool. To facilitate replacement after wear the hardened deflector plate G is detachably mounted on the supporting sleeve 'l as by means of a pair of oppositely facing side ears 8 affording slide grooves to receive the plate on top of a locating block 9 having an inclined mounting face for the wear plate 5. A set screw l0 is threaded in the block 9 and bears on the back of the plate to detachably lock it within its locating grooves.

High velocity particles striking the deflector 6 will carom at an angle approximately equal to the approach. `Witn the plane of the deiiecting surface at to the angle of the nozzle tip the shot blast projected from the tool will be in a plane substantially perpendicular to the nozzle axis and upon rotation of the sleeve the blast can be directed at any angle of rotation as desired or caused to sweep around throughout an entire 360 turn and on indefinitely. The nozzle may be traversed in the direction of its axis whereby all portions of deep holes or other inside surfaces may be subjected to the peening or shot blasting action. Thus this device mak-es it possible to shot blast or sand blast the inside of `holes that are inaccessible to the ordinary shot blast or sand blast devices.

I claim:

1. A blasting tool of the character described,

comprising a tool body shaped for introduction into a. hole whose internal surface is to be blasted, means to supply surface working material to the body for ejection under pressure and a deector positioned to direct the surface working material angularly of the body and mounted on the body for rotatable adjustment relative there- Y to.

2. The tool of claim 1 and a replaceable wear plate constituting the deflector surface and means for detachably mounting the same.

3. A blasting tool for introduction into an opening whose internal surface is to be blasted including a tubular body having an ejector chamber therein, means to lead fluid under pressure through said chamber, means to connect said chamber with a source of `solid particles, an ejector nozzle on the end of the tubular body, a sleeve fitted to the body for rotational adjustment and projected beyond said nozzle and a deflector carried by said sleeve in alignment with said nozzle internal surface.

4. A tool for axial insertion within a hole to treat the internal surface of the hole, `comprising a tubular body containing means for flow of surface treating material and terminating in a delivery ejector, a member telescopically tted to said tube for axial and rotary adjustment relative thereto and deflector means carried bysaidmember for cooperation with said delivery ejector in directing the treating material in selected laterali direction as determined by member adiustmmt position.

5. Shot blast means for compressively stressing the interior surface of an opening, Accmnr-rsi-mg fa conductor member for flow therethrough of shot blasting material, said member terminating in 2a discharge end insertable Within the opening Whose internal surface is to be compressively stressed,

a deector cooperating 'with said discharge end 20 4 to direct the discharge of said shot blasting material laterally from said discharge end for impingement on said internal surface and means mounting the deflector for relative ,rotation circu- 5 larly of the member.

JOHN O. ALMEN.

REFERENCES CITED The following references are of record in the lo ,file of this patent:

UNITED STATES PATENTS Number `Name Date 108,408 T'lghman Oct. 18, 1870 15 1,673,149 Lawrence Sept. 16, 19.13

u 2,392,897 `Archer Jan. 15, 194?- FOREIGN PATENTS Number A Country Date 370,068 France Jan. 28, 1907 

